A sanitary washing device that includes a radio wave sensor detecting a user is known. For example, the entrance of the user into a toilet room, the exit of the user from the toilet room, the user standing in front of an open toilet seat (e.g., the user performing standing urination), etc., can be detected by the radio wave sensor.
The sanitary washing device can execute functions of the sanitary washing device based on the detection result of the radio wave sensor. For example, when the sanitary washing device detects the user entering the toilet room and approaching the toilet, the sanitary washing device automatically opens the toilet lid. Also, for example, when the sanitary washing device detects that the user has finished standing urination and has moved away from the toilet, the sanitary washing device automatically closes the toilet seat and/or the toilet lid, automatically flushes the toilet, etc. It is desirable to suppress the decrease of the detection accuracy of the radio wave sensor of such a sanitary washing device.